Walt Disney Pictures' Tron: Legacy sequel is slowly moving forward. The Studios has drafted in screenwriter David DiGilio [Eight Below] to the untitled Legacy sequel. HeatVision report that Legacy writers Adam Horowitz and Edward Kitsis were expected to return to script the project but they "got waylaid" by commitments to their upcoming TV series Once Upon a Time. The site also suggests that the decision to make a sequel may depend on the performance of Tron: Uprising on Disney XD, which airs in 2012.